this is just my 2 cents-

But Oh Boy...I would be LIVID. First of all, what did he need to tell this to his life long female friend for- was the call THAT eventful? Nope- I would be upset, just NOT cool. I also don't like to make excuses for someone as to why they did something. So- You can't tell your wife that your ex called- but you can tell a female friend? That would make me wonder.
DH and I are very old fashioned about certain things and neither one of us have best friends/ close relationships with the opposite sex. I realize some people may judge us for that but I could care less, you have to do what works for your specific relationship and this works for us. That being said, I don't know what agreements you and DH have- just answering your question- yes I would be very angry and would want to know why he couldn't tell me but felt he could go to another female. Why did the ex call? I absolutely validate your anger. You have every right!!!